Bacteria are everywhere—on you, in you, in the soil, and yes, even in the wilderness’ cool, refreshing water sources. In fact harmless species of these single-cell organisms exist naturally in the backcountry’s rivers and pools. But humans and animals can carry harmful bacteria as well, and spread these pathogens to the water, making it risky if you happen to drink from the wrong place at the wrong time. Some of these bacteria are the same notorious headline grabbers associated with foodborne outbreaks or epidemics after natural disasters. We’ll discuss those and others, but first a few general facts.

Research backcountry water treatment and you’re sure to be warned about cryptosporidium or “crypto.” And for good reason. This microscopic protozoan parasite is one of the most common causes of waterborne disease in humans in the United States. Like the parasite giardia, crypto is found in water sources worldwide, and affects individuals differently. Fortunately, the disease it causes is rarely life-threatening in healthy adults. In fact, some 80% of the U.S. population has had cryptosporidiosis at some time, according to the FDA. Still, its symptoms are nasty enough that you’ll want to take strides to avoid it on your next backpacking trip.

Earlier this year, we gave you a behind-the-scenes look into the world of MSR’s on-site water research lab in this article. The microbiology lab was established in 1997 and has been dedicated to quality control, as well as researching, developing and testing water treatment solutions for outdoor users, the U.S. military and citizens in developing nations ever since. Recently, The Gear Institute stopped by to take a tour of the facility and find out why we go through such thorough testing on our water treatment devices. You can read all that The Gear Institute learned here.